Don’t make it your goal to number close
I agree. The only reason to collect a phone number is after getting an agreement to a future date. Propose the idea for the date and specifics for it in person. It's easier to sell a woman on the idea of going on a date with you while she's with you in real life as compared to selling her on that idea behind an electronic smartphone screen.
There's a big difference between a chance meeting with some cutie at the grocery store vs. walking up and down the same busy strip dropping pickup lines on any 7 or above.
Yes, there is a difference.
In 2012, Roosh called street approaching the most difficult approach venue.
In some USA cities (mainly in the Sun Belt region), pure street game isn't even much of a possibility. These are car-centered cities and there are few (if any) good streets with enough foot traffic for doing approaches. The best USA cities for pure street game are the older, more pedestrian-centered cities such as New York, Boston, Philadelphia, and Chicago.
In Sun Belt cities like Dallas, Houston, Phoenix, and Nashville, the better "street" type alternative is urban path/park game. Doing approaches of a recreational walking path or at a park are also difficult too, though slightly easier than pure street game.
Doing dedicated approach sessions in a grocery store, mall, or bookstore is also inefficient. In a grocery store, a dedicated approach session means that the approacher will still go to the grocery store and buy some groceries, but the approacher will shop at a slower pace and linger around looking for approaches. In a mall or bookstore approach session, the approacher might not actually buy anything, but he will linger for an extended period in certain mall stores, the corridors between stores, or in a bookstore's aisles. I am someone who has done grocery store, mall, and bookstore approaches. All 3 are inefficient. Since I am reasonably good looking, most women I approach in these venues are not outright rude to me. I try to approach with IOIs but I have done plenty of approaches without an IOI. It's very possible to spend 2 hours on a weekend afternoon in a mall and not arrange any dates.
I'm not a very big proponent of the dedicated approach session. It's good to go to these venues and be open to approaching and an opportunity. Planning a portion of a day around an approach session is not a very good idea. However, it might be a better option than using a swipe app.
Start going out at night. The reason cold approaching during the day doesn't work as well as at night is because at night the people that are out at the bars and the clubs are there to meet and be around other people - the girlfriends and wives are all at home with their husbands, kids, or girlfriends having some sort of wine night. I don't know if your goal is to get laid, but women will be much more receptive at places like this where they EXPECT to be hit on. Combine that with a little alcohol to loosen everybody up and it'll be a much more natural interaction.
Nightlife venue approaching has its own downsides. Your point on this makes a lot of sense.
Non-bar approaching is inefficient but could result in a good girlfriend prospect. Nightlife approaching is a better tactic for fast, shorter term sex. It's somewhat difficult to find a longer term girlfriend out of nightlife venue approaching. If the goal is a longer term girlfriend, using nightlife venues for 5-8 PM weeknight happy hour approaching might be the better tactic. There will be fewer approach targets by doing this but it's possible to have more meaningful interactions that could lead to something more substantial.
A lot of this depends on goals.
There's another daygame venue that doesn't work as well as it probably should. That venue is gym fitness classes. Gym fitness classes are majority women and social expectation after a gym fitness class is reasonable. However, women don't seem very sociable after fitness classes, even weekend morning fitness classes when they probably don't have much to do immediately after.