Cashless and Cash Only Stores

Neither of these makes a lot of sense to me and the Philadelphia area has both, though the cashless stores are now illegal in Philly proper.

I get that cash is a source of loss (via employee theft) for businesses and that credit card service fees can be crippling, but to completely shut out potential customers by requiring only one or the other just doesn't make sense.  I try to leave tips in cash (since some restaurants take the fees out of the tip otherwise), and when I'm dealing with smaller businesses (like my local deli) I try to use cash to save them the fees. When I'm going out to a nicer restaurant, on the other hand, and the bill is going to be in the $50 per person, I want to use my card--in large part because I don't generally have or want to have that much cash on me.