Who is to say they didn't do a "proper calculation" and result in something close enough to €99 that they just rounded up/down to keep things consistent?
That's ofcourse possible, but there are many many services that pull this trick, and I would be surprised if dropbox was the only one that did the honorable thing here. And even if that's what they're doing, they should realize it gives a very bad impression and maybe round up/down to a different price. Literally anything else would be better.
I'm perfectly ok to have an English only product with a 30% discount, but I can't find the option.
(That said, looking at the streets in Seattle, I'm not trading my 20% VAT for potholes, crumbling sidewalks and aerial electric wires in a storm prone region, thanks)