You'll never prove it because at the time of purchase, the rules weren't posted like they are now. There weren't cell phone cameras, or even digital cameras you could use for a quick picture. The camcorders were just getting to the point where you didn't have to plant them on your shoulder to shoot.
When you walked up to the cash register with your if I recall correctly $8.00 mug and asked why in the world (no pun) would I pay this much for a $3.00 mug, you were told by the cashier that if you purchased it it could be used for life. That was when we bought ours in 1992. I guess at the time they never realized that people would actually haul those mugs back to Florida each and every trip! We do out of pride. Disney being Disney they decided they better tighten up if they were going to squeeze every $touridollar$ out of their victims so they made it for duration of stay and posted the rules. That's my best guess Yoda, speculation, or an educated guess on my part as to why nobody has posted anything yet.
Now my response to those who point at me and call me a thief:
If I bought a mug today I would not bring it back trip after trip because the policy is clearly posted. However that being said, I will continue to use my old Port Orleans mugs as long as I have them. I am going by the original purchase agreement, and regardless of how many people on an internet forum agree or disagree I know what I know and value my own counsel on this, and care not what others may think.:wave:
Without further adieu, Disney's Port Orleans Resort Mug, circa 1992, (Notice I didn't say Port Orleans French Quarter....
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