Yes, but if you invite people and you and the person deposit more than 10k dollars, both win 30 dollars each year forever. 
And good services charge fee. They don't lend users money. 

 Is there any way to spend directly in btc? i.e. by performing automatic conversion between btc and dollars or euros. 

 Yes, they even support lighthing. You can have a balance in BTC and use the card, the conversion is automatic. 

 I have a referral code if you want. Code: URT-BSN-KF