You can still buy coins.  If you go to buy a pack for which you don't have enough coins a window will open offering you the option to buy coins.  It's just not a menu selection from the main shop screen anymore.

That sucks, because someone like me who keeps a million or so coins on hand at all times might still want to buy coins sometimes.  EA/Popcap, you need to fix this!  Why would you make it so people don't/can't spend money????  That makes no sense at all.

@CJackson5083 You can order them in Origin.

56,000 COIN PACK

https://www.origin.com/en-nl/store/buy/plants-vs-zombies-garden-warfare-2/pc-download/currency/pvz-garden-warfare-2-56-000-coin-pack

120,000 COIN PACK

https://www.origin.com/en-nl/store/buy/plants-vs-zombies-garden-warfare-2/pc-download/currency/pvz-garden-warfare-2-120-000-coin-pack

280,000 COIN PACK

https://www.origin.com/en-nl/store/buy/plants-vs-zombies-garden-warfare-2/pc-download/currency/pvz-garden-warfare-2-280-000-coin-pack

455,000 COIN PACK

https://www.origin.com/en-nl/store/buy/plants-vs-zombies-garden-warfare-2/pc-download/currency/pvz-garden-warfare-2-455-000-coin-pack

I'm on Xbox one, will purchasing them from Origin automatically load them into my profile?  I logged into Origin using my EA account.

Looks like it's only for PC that way. 

Yeah, that's what I thought too.

You dont have the purchase option?  What country are you in?

United States, Indiana.  Playing on Xbox one.  It was there the other day, but it's gone now.  And I'm nowhere near having all the items in the sticker book.  There's no reason it has vanished on me.

And I've gone to sticker machines on both the plant and zombie sides of the backyard, as well as the sticker shop in between matches on multiplayer.  No purchase option anywhere.

Just as suddenly as it disappeared, the option to purchase coins has reappeared.  Must have just been a weird glitch.