Clique culture in small companies is pretty common. It might not be boys club but there’s no middle man to protect Devs from those in charge so there’s always going to be pressure to hang out if everyone is or to work overtime. You have to work in that clique culture but you don’t have to always say yes as long as you are friendly about it. The phrase “being firm” has never sight right with me for these as it’s the antithesis of friendliness you can be loose and say no and if it’s brought up again stay loose and continue to say no. You don’t need an excuse but a loose excuse is works well.

Security is obviously always scary but the tech landscape does not really have that anyway. Realistically if the only worry is it’s a small company and everything else is good, take it. If you find that you don’t fit into the small team flow, then you can continue looking in the future.