Whether paid or points, Platinum Elite receive a welcome gift. If you select points, at full service brands, it's 500 points; at limited service brands it's 200 points.
Front Desk associates are trained to know this. What you experienced is a training issue worth escalating because of the customer service implications. Marriott Rewards is a huge investment for Marriott because customers respond to awards redemption. The Arrival Gift is an incentive for continued loyalty.
After reconciling your account, consider e-mailing firstname.lastname@example.org. In the Subject: "Disappointing Check-In Experience Confirmation #12345678." Describe what took place and that you would like to discuss with management. Customer.Care will e-mail you back with a tracking number and route the e-mail to the executive office of the hotel.
When you speak to management, highlight the fact that the Front Desk associate who denied your arrival gift undermined Marriott's promise to you as an Elite guest, challenged you creating an unpleasant check-in experience, and prolonged the incident by causing you inconvenience to have to reconcile your account. Go on to point out that what happened illustrates a training gap that management failed to correct.
At that point, management should apologize and offer to buy you Bonus Points to make it right. If nothing else went wrong, you should be good. If the Arrival Gift was among other incidents, demand a total refund of the points redeemed for Marriott's failure to deliver upon your expectations of service. This will make your point very clear.
We work very hard to pay the rates to earn points and Elite level and so our expectations for service given Marriott's promises is reasonable and justified. Marriott knows this and appreciates our loyalty - that's why there's Marriott Rewards.
Let us know how you make out.
I have stayed at one particular Marriott -both using points and paying for nights- and every time I use the points they enter the arrival upon check in - and when I check the site a few days later they are not posted. I have brought this up to the hotel many times, I have written the dates I am missing the arrival points - and still nothing. I have three different dates STILL without the arrival points applied. I am a platinum member and have achieved my nights needed this year to remain as such. Advice???