Why are pro players getting 10 bans first.

Did you not read the article? It explains exactly why they are getting bans first

Organized Play vs Matchmaking considerations We think improvements to the pick/ban system can offer multiple benefits. Those will be somewhat different in pro play or other organized play, than in regular games though. In organized play you’re playing with a consistent group, you know who your opponents are and what they play, and you may even have played against them before. In matchmade games by contrast you’re adapting to a new group and don’t have any initial information about the team you’ll be facing. The needs and benefits of each context’s somewhat different as a result.

And

What about regular matchmade games that use bans? Revised pick/ban for regular play will come somewhat later than the changes in organized play. We’re still assessing what style of pick/ban changes makes the most sense for regular games, given the different circumstances (unfamiliar allies, lack of information about your opposition). Shifting to 10 bans still has a lot of appeal, in particular because it allows one ban per player giving each person equal agency in the ban phase. Goals of bans are somewhat different though (e.g. you’re not banning the unusual pick you know the enemy team likes to run). The amount of time it takes to get into a game’s also a particularly big concern for regular games, given we’re already getting a lot of feedback that time from pressing ‘Play’ to actually starting the game feels too long. Some of the options we’re looking at include reduced time in champ select as a focus as a result. We should be able to talk more about our thoughts on pick/ban changes in regular play early 2017. In the meantime if you’ve got any thoughts on pick/ban, whether in pro or regular play, please do let us know!

Because they will be relegated to a single client. We can't have 10 bans if some players are using the old client still because it would take extra work to implement it there, and they won't do that because it will simply be wasted effort as soon as it goes away (like making a skin for a champ getting a VU in a few months).

riot likes money only thing to it