Do the maths!
'Pro mille' means 'per thousand'. 1.5 pro mille would be .15 percent. A seasoned drinker would hardly notice that blood alcohol level. Walking would be no problem at all, I think. On the other hand you might well show obvious impairment.
Yes, people are mean and unfair to pilots, because they think we are lucky to have glamourous, overpaid jobs. Life is unfair. Get over it, but not by having a few drinks too close to reporting time!
The German MPU (nicknamed 'the idiots' test') is a real nightmare. You even have wealthy Germans spending serious money with dodgy operators of driving schools to show foreign addresses to get a license without having to go through the test. Basically you will have to undergo it for various offences that hint at your having a personality that makes you inherently unsafe (busting the speed limit by a hell of a lot, driving with excess alcohol, etc.).
And just to make things really fun, the Germans operate a system like the USA's, where certain driving offences must be reported when you take your pilot's medical, when you will lose your license. Or else, you don't report, they catch you and then you lose your license.
I used to be a fairly naughty boy. Then I invested a lot of money and effort in getting a pilot's license, when I had to weigh continuing to have fun experimenting with self-medication versus finding myself suddenly grounded, perhaps for good. That was a bit of a no-brainer, really.