Not a cash advance and you would get 5 points. Its a purchase.
Your problem is getting Acme to accept Amex for LARGE gifr card purchase.
Many retailers will require cash for Large $$ amount girts gards.

Did you know the highest denomination is $100 and I think fee is $6?

Actually, Amex will sell you an aggregate $1000 in a strict 14 day period, Your fees will be lower. Maybe as low as $16 for 3000 points. I f you try to do this for 50,000 a year on various cards, they will shut you down. Terms say 'intended fro gift giving only"

If you ewant to buy $20,000 a year, you should be ok as long as you are a long time profitable customer.

Of course, Amex will only give 3 points, not 5.
Unlike travelers chek card and paper travelers checks, these are not considered cash equi. by AX.

You can't take money out of an ATM. Although the Paper gift Checques can be deposited, cashed.
SO American Express will be happy to sell you more than $1000 at a time with lower fees.

You will get Hilton points ( only 3X, not 5X).
This will not flag your account.

You can also but 40,000 Hilton point on HHonors website ata penny each. So 80,000 between now and january.
$800.

The Acme is about the same cost per point and I doubt you will get more than $200 -$400 G.C.'s without making them nervous