After you adjusted the inflation and all that, it's no longer the case (in the US at least).
1 Gone with the Wind MGM $1,507,252,900 $198,676,459 1939^
2 Star Wars Fox $1,328,772,200 $460,998,007 1977^
3 The Sound of Music Fox $1,062,418,700 $158,671,368 1965
4 E.T.: The Extra-Terrestrial Uni. $1,058,233,300 $435,110,554 1982^
5 The Ten Commandments Par. $977,260,000 $65,500,000 1956
6 Titanic Par. $957,460,300 $600,788,188 1997
7 Jaws Uni. $955,468,000 $260,000,000 1975
8 Doctor Zhivago MGM $926,050,500 $111,721,910 1965
9 The Exorcist WB $824,842,300 $232,671,011 1973^
10 Snow White and the Seven Dwarfs Dis. $813,140,000 $184,925,486 1937^
11 101 Dalmatians Dis. $745,382,700 $144,880,014 1961^
12 The Empire Strikes Back Fox $732,427,600 $290,475,067 1980^
13 Ben-Hur MGM $731,080,000 $74,000,000 1959
14 Return of the Jedi Fox $701,683,200 $309,306,177 1983^
15 The Sting Uni. $665,005,700 $156,000,000 1973
16 Raiders of the Lost Ark Par. $657,538,200 $242,374,454 1981^
17 Jurassic Park Uni. $643,095,600 $357,067,947 1993
18 The Graduate AVCO $638,362,600 $104,901,839 1967^
19 Star Wars: Episode I - The Phantom Menace Fox $632,800,500 $431,088,301 1999
20 Fantasia Dis. $619,504,300 $76,408,097 1941^
21 The Godfather Par. $588,762,300 $134,966,411 1972^
22 Forrest Gump Par. $585,950,300 $329,694,499 1994
23 Mary Poppins Dis. $583,236,400 $102,272,727 1964^
24 The Lion King BV $576,149,200 $328,541,776 1994^
25 Grease Par. $573,836,300 $188,389,888 1978^
26 Avatar Fox $558,179,700 $558,179,737 2009