In Spider-Man: Homecoming, Whilst Tony Stark is somewhere in India, some lady is shown putting flowers around his neck. Looks like that lady is marrying him or something.
Why is the lady putting flowers on Tony Stark?
According to The Ultimate Guide to Indian Flower Garlands they act as:
religious symbols to honour gods or even as a symbol of respect to a distinguished guest.
They're not just a wedding symbol.
Garlands are used to honour guests when they arrive. Indian culture believes in saying “Athithi Devo Bhava”, meaning “Guest is God”. Since the Gods are honoured with flower garlands, likewise flower garlands are used to welcome the guests. This can be seen whenever foreign dignitaries arrive in India. The guest of honour at an Indian event is always garlanded.