foodary or foodery
The Ampol service stations have chosen foodary as their corporate name for their food outlets. This seems surprising and, to be frank, uncomfortable and unconvincing.
The –ary ending in English is one used to represent the Latin –arius (an adjectival ending) or – arium (a noun ending) implying ‘having a relationship or association with something else’. Thus we have adjectives like elementary and voluntary, nouns like adversary and secretary. In particular words with this suffix can be linked to food sources, so aviary and piscary and granary. But these are old words. The suffix –ary is not what we call a productive one in English today.
By contrast the suffix –ery has been charging ahead, particularly in American English. Traditional items have been adoptions from the French with a respelling of the ending, for example, battery, bravery, cutlery. Later borrowings from French retain the French form and a certain French flavour. A patisserie is never going to become a patissery. Mais non!
Alternatively the –ery words are nouns linked to a person in a particular occupation where the ending is really a combination of the agentive –er and –y, such as bakery or brewery. The ending shifted from people to things, so pottery, crockery, and machinery. It could also be added to animals to provide a noun for the place where animals lived, such as rookery or piggery. But in modern use the Americans took bakery for their starting point and added such items as beanery, boozery, eatery, cakery, and lunchery.
I think that foodery clearly belongs in this set of words which is why the spelling with –ary seems so unnatural.