They have avery big carrot... 40B+ investment in Indian Market...
That's one way to look at it... Arabs from GCC states invest all across the globe, provided country /company is open for investments.
World of international investment is quite complex, obviously all the hassle is to earn legitimate profit, but if it swells to reasonable volume, it earns investor a leverage to influencing economy /policies of respective state. Imran Khan in his recent speech mention some thing like this with regard to his lender (IMF).
This is why various states have laws to limit investors control over local companies.
Beside all this there's a competition in investment, where first come first win type of laws command investors. If it's not UAE, it will be China and if both are missing than it's Indian investors coming to swallow the un-contested loaf.
Advantage to invest in India is that competition get slim.... while Arab investors can operate there as it's their backyard, while Arabs know how to circulate their capital in todays business world, where no business model is sustainable, over longer period of time.