Normally I'd be why take the chance but every $ counts and I have the fluid. And it was in those tubeless tires for over 40 years and when I removed the tires (switched from turf to Ag tread) I was astounded to see spotless wheels on the inside. The outside of the wheels looked like what you'd expect on a well used 46 year old tractor.
I guess you can say I'm being cautious as this time I decided to use tubes wen mounting the new tires. Hopefully upping the chances of a trouble free next 40 years. Those darn tubes cost me $20 each plus the $12 each for mounting the tires with them.
I guess I could have installed the tires w/o the tubes and spent that money on say washer fluid but the tires I put on while quite good aren't new and I hate tires that loose air/water.