The Hamptons -- Kardashians Will Be Cash Cows ... Says Local Politician

The mayor of ritzy Southampton has beef with "Keeping Up with The Kardashians" -- claiming producers lied to him -- but he also knows the family's about to help his town make bank, and as they say ... money talks.

Mark Epley tells TMZ he was initially told by producers Kourtney and Khloe Kardashian would NOT be opening a new Dash in his town while filming there this summer, but it turns out a pop-up store is in the works. He says he has no problem with it -- he just wishes producers hadn't lied.

Epley says some residents are worried about possible traffic issues with the Kardashians in town, but he thinks the financial gain from the exposure will be huge -- record sales for Dash, and a sales boost for neighboring businesses.

As for reports the Kardashians are getting their space rent-free ... Epley says that's not true.

As TMZ first reported, the Ks had quite a difficult time finding a place to live in the Hamptons for the summer ... with most of the town refusing to rent to them.