Maybe its just me but I don't really see any "religious" practices from other faiths being added to the ceremony but rather cultural practices as touches to their special day...
I agree, its more a reflection of culture than of religion. It isn't like they are trying to claim they have knowledge or belief in Judaism or such. You can show respect for other cultures. I went to an East Indian wedding, I took off my shoes, and had a scarf to cover my hair, I am not sikh, but I showed reverence to that culture.
The glass I have heard as being said that love is precious, let the vows that be taken and marriage formed, be as hard to break, as it would be for the glass to be made whole again. It is beautiful symbolism, which has nothing to do specifically with the Jewish faith. There are many interfaith ceremonies, Christian/Jew, where a priest will have them break the glass. It is merely symbolism of the union.
I love handfasting ceremonies as well. There is such beautiful tradition, I think some still do it in Scotland (well tied for the ceremony at least). The whole sharing of honey mead, could be considered similar to the sharing of sweets as mentioned.
I don't know if this story is true, but I don't think if it is, that is has to be such a cause for stir. Now a days brides and grooms are always personalizing their weddings. They write their own vows, they serenade each other, some light candles, include their kids, release buttteflies.... Lots of these have roots in ancient tradition, but we don't think of it. Yes this is being televised, but it is still their wedding, and it shouldn't be too shocking they might want a few personal touches to it. And considering their travels and interests, including other cultures is a reflection.