Yes, tapes are very useful.
Sometimes the content is interesting, if from TV. Some of us collect old shows and old commercials -- things not available on DVD.
But more importantly, the tape can be reused for the clamshell. The actual tape is discarded, and the shell used to repair other tapes. Many expert pros and hobbyists will even remove a VHS-C tape from it's shell, and place it into a full shell. This is because of the mechanics of a VHS-C often lead to an "eaten" or feathered tape. Transferring it to a full shell is a way to avoid such problems.
Just last week, I had to buy 6 new tapes to reuse for the shell, as I'm now out of recyclers.