They are implying that when faced with the choice of paying €30 for a couple of pints or smoking free weed that many will choose the latter which will impact alcohol sales in bars to a significant degree.

I was joking here a bit, but:

• A big crowd of people has suddenly a lot of weed.
• People in Berlin like to go to bars and like to smoke weed (a fact)
• Suddenly there's a lot more weed, many people more are smoking it either in the bar (allowed in a few places at least in Neukolln) or outside the bar (about every other place outside Neukolln)
• Fun.

So it was my take on laughing a bit about the winter 2024...