I have had the same thing happen to me! they guy said he wouldnt sell them to me unless i was feeding it to a bird! lol, so I went back 10 min later and said I had a love bird, funny thing is I dont have any idea if lovebirds even eat meal worms, and neither did he!
next time they tell you that, call Bull Sh*t on them, and ask for proof! if they dont provide it, have a little bit of fun with them! Procede to ask them if they believe in other urban legends (because thats all it is!) like checking in the backseat of cars for axe murders, pop rocks and coke ect..., infact bring a bottle of coke, and a package of pop rocks with you, and bet the pet store worker that if you can down the coke and the pop rocks and Not have your stomach explode (trust me it woant i've tryed it!) he will give you the meal worms.... 
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0.2.0. Leo
1.1.0. WTF
0.1.0. Irish Setter
2.2.0. Holland Lop Bunnies
1.1.0. House Cats
Too Many Fish!
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