It's simple, really.
These same merchants that find Christmas, the word, offensive, still want Christians to buy their Christmas presents from them.
Christians who find liberals efforts to eradicate all signs of Christ from public discourse bewildering or threatening simply don't want to risk offending those same merchants by spending their offensive Christmas dollars in their stores.
Signed,
The Clarifier :-)
>Employees are free to use any holiday greeting that they feel is appropriate (no official policy)
I think this is the best solution!
Some employees are Christian, some are not; ditto the customers.
Leaving it up to the individuals, that seems the least intrusive. If I were working in a store I'd be annoyed if the management told me what I had to say!
For myself I am happy to get any cheerful & well intentioned greeting, at any time of the year.