Although you can’t assign a dollar value to a ‘thank you’ per se, keep in mind that these two little words go a long way. Whether you are receiving something old or something new, simply saying ‘thank you’ makes the giver feel appreciated and special. Not acknowledging, on the other hand, presents itself as an affirmation of entitlement and shows a lack of social graces. If you want to ensure that you are easily forgotten by the giver for any future considerations, just neglect to thank them.
If you want to be the better person and show respect and appreciation just say “Thank you!”