XKCD posted quite nice comics with a reallife problem behind them. It is very likely that some Web-services do as described, either sell such info to third parties or use it for evil purposes. Our recommendation is if you cannot trust some of the websites, choose another unique password for them. It would be even wiser if you had different passwords for all websites you visit. Some even unimportant websites can aslo be cracked and even if they (better to say your data stored there) have no value at all, your password, can be tried for Facebook or LinkedIn, hopefully in vain.