I've seen hops extract (hopfenextrakt) on the label of only one wheat, which was Schfferhofer dunkelweizen. All others that I've seen say just hops (hopfen), so I'm assuming until told otherwise that if they use hops extract it has to be mentioned on the label.
More than any other beer, it was Hefeweizen that got me into brewing - it was a chance purchase of a couple of bottles of Schfferhofer which set me on the path to beer enlightenment and eventually all-grain brewing. Consequently, hefeweizen is the style I have returned to time & again, and also the style I've had my best competition results with.
IMHO, you can make a great hefeweizen by brewing as simply or as complex as you like.
A basic crisp, pale & refreshing hefe like Schfferhofer Hefeweizen can be as simple as 60% wheat malt, 40% pilsner malt, infusion mashed at 67 or so, OG of 1.048 - 1.052, and bittered to around 15 IBUs with any noble hops. Use WLP300 or Wyeast 3068 at 18 to 20C.
For a more complex hefe resembling Franziskaner, add a little bit of carahell and munich, and use a decoction mash. Either a single decoction to go from 55C to 66C or so, or better still a double decoction starting at a ferulic acid rest in the low 40s, then to a brief protein rest at 55 then another decoction to 66 will give great malt backbone and enhanced phenolics. I made a beer with the double decoction schedule, 60% wheat, 33% pilsner, 5% munich and 2% carahell and wyeast 3638 which was very close in flavour to Franziskaner. Erdinger can be adequately reproduced with a similar grain bill, but with K-97 at the upper end of its temperature range, around 22C, where you get some mild banana from this yeast.
To get more into the Schneider style you need to go darker again, by upping the munich malt proportion, using at least double decoction, and maybe a hint of melanoidin or a dark crystal like CaraAroma (but only 1% or so). A little bit of flavour hopping (like 5g of Tettnang at 15 minutes) helps with the more full bodied & flavoured hefes as well.
cheers,
Colin