Several auctions popped up on eBay, with one listing even reaching more than Â£1,000.
The gift bags were given to members of the public who were invited to share in the couple's big day on May 19 in the grounds of Windsor Castle, but not the 600 chapel guests.
The seller of one listing, which reached Â£1,020,00, wrote they had received "this Wonderful gift bag for guests", and added: "I forgot to mention all money raised will go to charity."
Prized contents included an order of service, large chocolate Harry and Meghan coin, fridge magnet for the wedding, map of the castle and where to go, bottle of water, special guest badge, discount card, Harry and Meghan wedding shortbread and finally the hessian bag itself, they said.
Another seller, who so far had a bid of Â£458, described it as a "piece of history and Royal Wedding memorabilia given to celebrate a very special day".
They said they were selling their "goody bag for 'golden ticket' guests invited to the Royal Wedding".
The Chartered Trading Standards Institute said that such transactions are private sales between consumers, and as such are not covered by trading standards.
More than 110,000 people filled Windsor's streets during the Duke and Duchess of Sussex's wedding, according to a new estimate from authorities.
The influx for Harry and Meghan's wedding meant 13 tonnes of rubbish was collected, the Royal Borough of Windsor and Maidenhead said on Monday.
Some 67,000 train trips were made in and out of Windsor's two stations on Saturday, the council said.
Bunting designed by schoolchildren measured nearly two-and-a-half miles, while 746 temporary toilets were used, according to a spokesman.
Based on new information, the council revised its estimate of those in town during the day's festivities upwards from the 100,000 it initially stated.
The ceremony was also a hit with television viewers, with an average of 11 million watching on BBC or ITV at any one time.
Deputy leader of the council Phillip Bicknell said: "We are honoured they chose Windsor for their wedding and seeing the pictures and footage of our town packed to the rafters with well-wishers enjoying the sunshine has proved what we knew all along - Windsor knows how to throw a royal party like no other."