There are a lot of good UHF wireless systems available now that avoid the commercial bands altogether. That being said, a good VHF system should be rejecting most everything other than other mics that might happen to be on the same frequency in a close area, which is usually very unlikely.

I don't want to make any aspersions on your VHF system, but i would recommend upgrading to something better. Usually anything that lists under $400 for a mic, transmitter, and receiver is pretty much useless. The fact that you're getting that kind of interference indicates that you have low grade receivers that are tuning in a large range of frequencies rather than being carefully tuned to the transmitters. If you're hearing commercial radio interference then you actually have FM systems that are far worse even than VHF. Someone may have sold you a line of bull along with cheaper systems.

In our church we have a few Shure LX systems that are true diversity* and operate in the 176MHz band. We also have a couple of their newer UHF systems which i think are 900MHz. The VHF systems cost around $500 each and our interference experience with them has been an occasional tiny static crackle perhaps no more than once a year. The UHF systems have yet to experience any interference at all, but they were around $700 each. Note that the systems we have are pretty much cheap bottom-of-the-line equipment. Looking at Shure's website i see their new UR series UHF systems run in the $3900 to $7300 range (ouch).

Check out ebay. I often see used LX systems in good condition selling for $200 or less.

*Diversity systems transmit on two frequencies simultaneously. The receivers pick up both signals and instantaneously switch between them to always bring in the clearest signal possible. This alone eliminates most of the common problems.