As a resident of SF I find coffee-shop laptop users to be a pest in busy cafes. Coffee shops are a great social environment, and dominating a seat for an extended period of time while you are immersed in your computer runs counter to that culture.
This is a design problem and Starbucks has it right; uncomfortable and small seats and tables. So you can sit, but anything past 20mins and you want to get up and move.
The other side of this, however, is that if I need to work somewhere and I don't have an office, where can I go? 2 people cannot comfortably work in my dinky condo (I can barely live in it...) and I don't want to pay $100+ for a co-working space. Compared to a $2.50 coffee, that's insane!
It will depend on your city, but public libraries are usually fantastic. The wifi is free, the seating is spacious, and everyone is there with a purpose. They also cost nothing and you never get the "am I loitering?" feeling that you get in coffee shops.
University libraries can also be good, but be mindful of the date. If it's exam season I tend to avoid them simply because students should have priority to the libraries they are paying for.
I think this entirely depends on the vibe and setup of the cafe. There are some I frequent that are clearly not the place to whip out your laptop and start working away, but there are others that openly cater to that crowd and are setup towards that end. Heck one of the better ones I frequent is putting in Google Fiber and wired gigabit connections for the folks that like to work from their shop.
I agree, some coffee shops like it, apparently somehow they make the economics work (the one next to me calls itself a "Platform for Entrepreneurs," ugh).
I'd like to see someone open a cafe that has a communal-only seating policy, perhaps even you are assigned to a seat in one of the communal seating areas, no laptops. The cafe promotes active engagement and conversation amongst people who do not know each other. A return to the original purpose of the London coffee house -- a place to debate[1].
There are plenty of coffee shops where people are buried into their laptops already, but as this article demonstrates, some people really do want to talk to people they don't know, but they find it tough to get out of their comfort zone. If there's a space where this is encouraged and promoted, I think many would welcome it.
One of my favorite coffee shops in SF has no wifi and is explicit about it. It's fantastic. Doesn't stop anyone from tethering, obviously, but it keeps the laptop warriors out all the same.
