I’ll be perfectly willing to concede your point if you provide data that some significant percentage of gas taxes is spent on bike paths.
I’ll agree up front that mass transit subsidies and diversions to general fund are a big problem. I suspect they utterly dwarf any money spent on bike trails, but for some reason those are what tend to infuriate motorists most.
One bike trail near me was laid out along one side of a new toll road. The right of way was already paid for, so no cost there.
I’d be quite surprised if the bike trail construction added even 1% to the cost of construction.
Do you understand that this is how multitudes of "extra" government spending is justified? It is one item, just an easily understood example, of massive amounts of of "extra" spending justified from a big expense and continually spent on others.