Pricing policy

Dears,

Im from Czech republic (middle of Europe) and I checked offer from Microsoft store this weekend about Lego games and because Im relatively new here (account started after Xmas 2020) I have 2 main questions to figure out, how this world works:

1) "Huge Lego Sale" is not so huge - the prices are the same like before, maybe to add some other titles (I'm checking Lego games about 1x per month because of my children). Why are the prices the same like before?
2) I was also accidentallylogged into an USA market with real Lego Franchise sale (80%) and the prices are there also VERY different. For example Lego Harry Potter Collection costs here in Czech republic 599,50 Kč - in the USA its for 7.99$, Jurrasic World here for 299,70 Kč, USA for 4,99$, Star Wars The Force Awakes Deluxe edition here for 359,70 Kč, USA for 5,99$ - currently exchange rate 1$ = 21,52 Kč. How is this possible?? Dont say anything about PPS index which is much higher in USA.... OK I can understand situation with DVD distribution, but I own Xbox series S with only digital content. So the virtual distribution of the game will be the same worldwide I suppose ... only to send digital key ... why we have prices here for the same product 3,5x higher?

...and one supplementary question to that. Can I ask my friend from USA to send me game key and use it here?

Thanks for answers

Jiri

:)