Please Connect The IN-Game Shop To The Website?

Technically they could, but the majority of mobile players don't visit the games website, participate in forums, etc.  It would be for a very small minority of players on Mobile so be a lot of work for few results.  This game also has it's currencey separate from their other games that have web shops so it may end up confusing people.  Realistically it's far easier for them to use iOS and Google playment systems on your devices than to link that to a web site as well.  Maybe it's fine in France, but in the USA their web shops have always had issues making it very difficult to top up at times.

If you just mean to let you shop with what you already topped up with in the game that might work, but again most mobile players only do their shopping in the game's app and wouldn't visit here outside of it to buy.  It probably is too much to do for too little result.

I'm not trying to trash your idea or anything, just saying why it possibly won't happen.  If they think it's worth it in the end and they'll make money sure they'll do it, but if they know much about the mobile audience they probably won't.