My answer is NO! The person, regardless of whether they are aware or not, is actually wishing you have happy HOLY DAYS! That would actually be the PREFERRED GREETING prior to Christmas Day! Why? Because prior to Christmas Day it's NOT CHRISTMAS YET! The season prior to the Christmas Season is Advent, not Christmas. Advent is a time of anticipation and penance - it is NOT "Christmas." The Christmas Season starts with Christmas Day, and then we have the "Twelve Days of Christmas" which run from December 25th through January 5th. January 6th starts the NEXT season in the liturgical year, and that is the Season of Epiphany! Some traditions include Epiphany with Christmas extending to "Candlemas" - which traditionally is the celebration of the Presentation of Jesus at the Temple. It is celebrated the Sunday closest to February 2nd.
How About "Merry X-Mass?"
Well, here again, NO! The "X" is traditionally a Christian symbol for Christ! So, in reality, they have not "removed" Christ from Christmas in using X-mas!
Be Joyful! Celebrate Christ!
It is my opinion that we should not get all caught up in negativity. The world has far too much of that as it is. Let us see joy and hope, especially in this season of Christmas! Consider how your words and actions appear to others. Are you presenting a good Christian face to the world? Or, are you presenting a Scrooge-like face (prior to his epiphany)? Think about it and BE HAPPY!
Merry Christmas to all and peace to men of good will.