why so many 9mm guns in movies/tv

[k9870]

ive noticed the beretta 92 is overly common in movies but have noticed another standin, the sig p228

the sig is used to replace the 229 a lot, even different calibers

noticed in

24, in the line of fire, the sentinel, eagle eye, xmen, transformers, all secret service have 9mm sig 228s even though its a 357 229 in real life

never seen a 357 or a 40 in a movie /tv

wondering, are 9mm guns easier to convert to blanks or something? why so much usage, besides people liike john woo who wont put reloading in movies