Generally I don't think you'll get that much use of the stem cut-out. The WDW version does have the cut-out but also has a depressed indentation for a flat-bottomed cup. As mentioned above, beer and most frozen drinks (exception- the slushie in France) come in a flat bottomed cup. Wine comes in a glass with a teeny tiny stem (see attached picture - sorry, not the best angle) and is fairly sturdy and easy enough to carry on a regular tray. Champagne/sparkling wine and the slushies in France do come in long-stemmed glasses. If you look at the Disney Food Blog or one of the other sites and scroll through pictures from last year (or search YouTube videos) you can get a good idea of the various cups. For those booths that offer flights (beer or wine), they typically do give you a small try to carry - cardboard or sometimes plastic.
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