The Little Shop /secret base
 

ive been noticing it more lately but a several sentais seem to use a restaurants as their base or its a little shop but regardless its usually a little shop -same with kamen rider wizard decade ect little shop of some kind no special technology just a shop.

It's almost always best to hide in plane sight.

Gorenger was also a restaurant called snack Gon. Abarangers were at the dino curry, Boukengers fronted as a museum and archival institute, Gekirangers had a whole sportswear brand as a front, Kyoryugers went ninja turtles on us. :lolol
Oh and Carrangers had their day job aka the auto shop, Megarangers had inet and their club activity room, Timerangers were an odd jobs office.

Maskman was different, they use a apartament as their base.

Even outside of tokusatsu you might see villains hide their base in plane site. Like in the series Animorphs, the Yerrk had a base hidden under a fast food burger joint. If the cover is popular enough who would ever think the place could be used as a base.

Because saving the world does not pay the bills.

It's a tradition. The first few Kamen Riders operated out of various Tachibana Tobei-run businesses: a bike club, a souvenir shop, and then a restaurant.