Is there a new word that means "philistine"?

Any good thesaurus will provide a plethora of useful terms with senses similar in various ways to the dictionary sense of 'philistine' you cited. Try WordHippo for twenty nouns and six adjectives. Your dictionary appears to be working, so you can use it to attempt to fathom the various shades of meaning of those twenty nouns and six adjectives, and perhaps even puzzle out how those shades of meaning resemble, and differ from, the meaning of 'philistine'.

Of similar terms for the dictionary sense of 'philistine', 'yahoo' may be best:

1. A name invented by Swift in Gulliver's Travels for an imaginary race of brutes having the form of men; hence transf. and allusively, a human being of a degraded or bestial type. (Cf. houyhnhnm n.) Freq. in mod. use, a person lacking cultivation or sensibility, a philistine; a lout, a hooligan.

["yahoo, n.". OED Online. September 2015. Oxford University Press. http://www.oed.com/view/Entry/231128?rskey=D6cHfM&result=1&isAdvanced=false (accessed November 24, 2015). Emphasis mine.]

A Google Ngram comparison of raw frequency data in the "English 1 Million (2009)" corpus suggests that the 'yahoos' have overrun the 'philistines' with a spike starting about 1990 that may be continuing today:

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For your idiosyncratic sense of 'philistine' ("A person whose buying power exceeds his or her cultural and spiritual needs"), to my surprise, there is a new word (just what you asked for) that approaches that sense:

Babbitt, n.²
....
Etymology: < the name of George F. Babbitt, the eponymous protagonist of Sinclair Lewis's 1922 novel.
allusive (orig. and chiefly N. Amer.).

A person likened to the character George Babbitt, esp. a materialistic, complacent businessman who conforms unthinkingly to the views and standards of his social set. Usu. in pl.

["Babbitt, n.2". OED Online. September 2015. Oxford University Press. http://www.oed.com/view/Entry/14196 (accessed November 23, 2015). Emphasis mine.]

Along with 'Babbitt' comes 'Babbitry' ("behaviour and attitudes characteristic of or associated with" Babbitt, noun, op. cit.), while 'philistine' must struggle along as best it can with 'Philistia' ("uneducated or unenlightened people collectively, philistines; the domain of such people; the community, culture, or lifestyle of philistines; philistinism", noun, op. cit.).

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You don't seem to want a phrase, but I'll offer a couple anyhow.

More money than brains

seems to express your idiosyncratic sense of 'philistine', and

he buys his books by the pound

works when a long, drawn-out version of the same thought is desired. If even longer and more drawn-out suits the occasion,

... in matching colors

can be readily tagged onto the end of the pounding.