Of course you shouldn't use a free VPN for anything sensitive, but to obscure your browsing data (like what you search for or what media you consume) it's completely fine.
> to obscure your browsing data...it's completely fine
You prefer taking your logs away from the potentially-prying eyes of regulated ISPs and giving them to an unknown, unregulated person? Free VPNs are a medicine that's--at best--only as bad as the malady.