Those things are gone now because the only reason people were doing them downtown is because they had to be there for work.
It's odd to suggest that people spending their money closer to home means shopping at large chain businesses, but spending downtown doesn't. Just because there isn't a Walmart in the city's corporate center doesn't mean you're patronizing Mom and Pop small businesses. You think that trendy gastropub with its gourmet hamburgers, cute waitresses that all share a suspiciously similar alt aesthetic, and tables full of people clad in business casual isn't a line item in some investment firm's portfolio?
Guess where the Mom and Pops are? They're in that "stripmall place" near your house.