Freebie proxies have a very checkered past. First thing like my dad told me you don't get something for nothing. Second this smells like the public proxies of the 90's and early 2000's. At the time they called them honeypots. You have someone who is capable of logging all your web activity by logging every request you make tied to your public ISP IP, the log being provided by in this case Glype.
You are better off switching to a Tor browser or subscribe to a trustworthy VPN provider.
Many people got busted by obtaining their logs from these "public proxies" in the day ,many times connected one way or another to law enforcement. Try an alternative and see what happens with Glype and other freebie proxies in the next six months or so. After all, someone or some organization is paying for the hardware, bandwidth, and it's management at a server farm somewhere. I don't see any charitable organization stepping up to fund this project, do you?