Lastpass like pretty much any modern password manager has zero knowledge of your encrypted vault so regardless of how crappy the service they physically cannot leak your data. This is the reason why encryption exists, to move secure information across not just insecure, but even adversarial channels.
When you use cryptography you go through all the hassle exactly so you don't have to have a panic attack when a company behaves stupidly.
When you use cryptography you go through all the hassle exactly so you don't have to have a panic attack when a company behaves stupidly.