If I had a chip I didn't want I would take it seeing its better than nothing.
Besides when you've maxed out stars and your main.. it's really not worth entering cw. However, it's not a problem to build up your tickets to perhaps get the chips which you want.
By Riot entering cw and fighting all the fights, he ultimately gets the maximum amount of tickets that he would like to get, then dropping out in the final cause he doesn't want the bad chip and the unnecessary leader cards and purple medals which is perfectly understandable! If it were me, I would also try to get the most tickets I could get out of cw. If he (Riot) were to bet like any other person, he would get much less tickets than him fighting which I personally see no fun in.



