The idea of a currency in the metaverse is an interesting one. Having a currency could fill the virtual world with profit and wealth, resulting in global econimical advancement. However, it could turn the metaverse into a beehive of money and business which wouldn't serve the common good.
Having this currency would be brilliant for all countries. If it was global and virtual, it would cause an economic boom, which would further advance big tech companies. With there already massive wealth they would be able to invest in other areas and cause development. For example, Alphabet ( the owner of Google and YouTube ) is already developing AI. Increasing Alphabet's wealth would help to develop AI, causing a boom of art and innovation. Also, having this currency would mean there was profit in the metaverse; without that there wouldn't be nearly as much incentive to build it.
On the other hand, having this currency could turn the metaverse into a massive advert for tech companies. Causing everything ot cost money would mean people would get less enjoyment out of it. Plus, different companies would compete to make more profit and the already long list of court appearances would triple. Companies and governments would squabble about tourist rights and other nuisances.