They do provide sth unique, because open source/privacy friendly alternatives are not supporting the same features to a full extent in one solution with a simple UX. And even Bing, as you mentioned and other competitors, fall short. I'm using Startpage (based on Google) and OSM most of the times and I'm happy with it, but sometimes I gotta check restaurant ratings or satellite view etc. Also route planning is way more convenient on gmaps even if I don't use it. There's probably more as well, which I'm not aware of.
Yes exactly, YouTube is the only google service I use almost everyday (besides Startpage).. but I wouldn't know what to do without it.