Well they are not the only celebrities promoting about ICOs and cryptocurrencies. I have seen some and I'm not sure if they are aware that what they are promoting is a real project or they are just concern of their pay  for their promotions. The truth is seeing a popular person promoting a certain cryptocurrency gives a big impact to that project. People are thinking that because they believe in that celeb they ought to believe also to what he is talking about. It somehow build trust in the part of the investors to the project the celeb is promoting. 

Hmm you have a point in your opinion I encounter a project that introduce by "Fake celebrity" I tried to research the background and goals of the project then noticing that this project are fake no celebrity involve at first.
Well being popularity of cryptocurrency no doubt even celebrities are encourage to enter in cryptoworld even without knowning the risky they will encounter.

We are always advice not to rely on the advice of others when it comes to cryptocurrencies investment cause it can be misleading, we have seen a lot of celeb promoting one cryptocurrency or the other but the fact is to make the right decision we must carry out our own research about a coin before we invest otherwise we may be mislead by hype and speculation.

If you are very much into Cryptocurrency you will not look at those celebrities promoting cryptocurrency but rather you will look at the platform and their roadmap, you will not rely on other people to look on where and what you should invest in, it's a complete disaster if you do that.

usually celebrity just want to promote when they get the endorsement, and i think that bitcoin will never endorse anyone to promote bitcoin, so if there are many celebrity that endorse bitcoin or cryptocurrency i think they promote for other platform or they want to share to another people

Agreed with you, Celebrities are too cautions of money and fame, they can promote any shading program in the name of financial reward. Have seen some celeb who sold out their trust just to get financial rewards, this attitude is very much found among celebrities, so, never take their words because they could be endangering potentials investors.     

What do you expect from Floyd, he worship money.

Celebs are always going to get paid for promoting something, they will even be paid for tweeting on their channel e.g. John Mcafee though he seem to be involve very much in cryptocurencies but he still is considered a celebrity and some of his followers worship this guy. Anything he says can impact what people will think of a project and you can see this from the previous projects he shills.

Definitely the project will pay those celebrity that helped in promotion, but there is one question i ask; for celebrity to promote the coins, will it give it express to be successful?  Of recent there were coins that celebrities promoted during their ICO and those coins all end in dust and scam. Celebrities can do anything for monetary gains even though they are not investing into that coins, just doing it to earn. 

Yes you are right, there is no point buying products or following investment ideas from celebrities. But, we can't ignore the fact that, they could introduce the product to a large audience. They could grab peoples attention. In ICO's case shilling makes projects popular and eventually investors would be interested in popular projects. That is why we have seen many people following celebs and famous investors.

Of course we will have to trust and value our own observation because even if celebrities are promoting something but it is not sure that if they use it personally or doing it only for money, but still many celebrities are using and investing in crypto currency which is good for both the coin and the celebrity, for me I think to some extent they can take part good part in development of crypto currency.