..... and at least some of 'em have gotta be legit: https://constative.com/lifestyle/hilarious-texas-signs-is-m/46/
Nothing unusual about those signs. I've seen some very similar. The buckle up sign is indeed a good one as are the ones about "Don't Mess with Texas" (about not littering). Texans have a sense of humor and use it all the time.
Love the first one, sent it to a former math teacher colleague.
'Deering banjos' 21 min
'One of my favorite' 1 hr
'Banjola' 2 hrs
'ID these tuners?' 3 hrs