Why aren't all modern vinyl releases 45s?

Often, artists have little say in how their recordings are licensed. Audiophile releases are a tiny chunk of the market and 45s are more expensive to cut, press and manufacture, along with additional expenses in packaging and shipping.

Steve Hoffman has said that the only real difference is that 45 LPs are louder. 

A good 33 is fine by me-- since my baseline is standard issue stuff. And 45 LPs are a PITA. Maybe this is about sonic spectacularity, but I'm not gonna buy some warhorse I probably already own simply b/c it was reissued as a 45 or on some new vinyl formulation. Indeed the last batch of MM stuff that Kevin Gray did went back to 33. 

Buy what you like. I'm not trying to persuade you otherwise. Just my take as somebody who has been around the block a few times (too many). 

@whart , I tried something like 10 times to get through. Would you like to recode the situation?

As for 45 rpm LPs, they are as a rule better sounding. The dynamic range is a little wider as is the bandwidth. Distortion is a little lower particularly at the inside of the record. If they are not pressed to the highest standards the noise they produce can be more annoying as it is pitched higher. It seems that more care is taken in the production and manufacture of these discs as their consumer base tends to be more discriminating. They cost more and require more exercise. An auto lifter makes life a lot easier. The Little Fwend is handily the best, highly recommended. If it is a well recorded and mastered favorite work it is worth it. The only other discs that can compare are the D2D's. 

Bill, cut it out. You know you need the exercise:-)

Nah, 45 is barely any better than 33 1/3. Just wait a little bit. I'm working on producing high fidelity 78 RPM discs. Two and a half minutes or pure sonic bliss. They will sound so great that the rest of your system won't matter. Coming soon

Contact me if you're a qualified investor looking for the next big thing.

It’s not worth issuing on 45 rpm vinyl unless it’s a top notch recording mix. I have a few from MoFi and Analogue Productions and they are superb. Very quiet, accurate and tons of image. Dream with Dean (Martin) by Analogue is amazing. But I don’t buy many 45’s due to the cost and as Blisshifi says having to turn the record over after just a few songs. 

Why aren't all modern cars replicas of the Mazda Miata?

A valid question, though I've learnt to save what remains of my hearing with earplugs when the roof is down. I bought an NA in 1991 and have put nearly 50k km on her during the 31 short summers since.

As for 45rpm vinyl, buy one of Reference Recordings releases of Doug MacLeod and you'll quickly see why it would be wonderful if everything sounded like that!